1. Field of the Invention
This invention relates generally to the field of inhibiting theft of computer programs, and in particular, to a method for determining theft of grammar code in speech enabled computer programs.
2. Description of Related Art
It is extremely difficult, if not impossible, to determine if a competitor has illegally copied, renamed and/or used grammar code developed by another company.
In the rapidly emerging field of speech enabled systems, encoded command grammars are becoming common. While simple grammars are relatively easy to develop, and are therefore of little value to the developing company, more complex grammars, including natural language and natural command grammars, are very difficult to develop. Such natural language and command grammars are therefore quite valuable.
It is fairly easy to determine if a competitor has illegally copied and reused a simple grammar simply by checking the file size and exhaustively testing the grammar to see if the grammar accepts all and only the valid commands from the original grammar. In many cases, these types of grammars have a very limited number of valid command, so exhaustive testing is feasible. It must be noted, however, that even if exhaustive testing shows the suspect grammar to have the same input/output properties as the original grammar, the testing has not conclusively proven theft.
For natural command grammars, though, the number of valid commands is for all practical purposes infinite, precluding exhaustive testing as a method for indicating even the possibility of theft. There is a pressing need for a simple method for conclusively determining theft of natural language and command grammars.